This application is based upon and claims the benefit of priority from the prior Japanese Patent Applications No. 2001-079388, filed Mar. 19, 2001; No. 2001-220266, filed Jul. 19, 2001; and No. 2002-035714, filed Feb. 13, 2002 the entire contents of three of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to a color reversal photographic material, and particularly, to a color reversal photographic material exhibiting improved color reproduction. More particularly, the present invention relates to a color reversal photographic material superior in faithful color reproduction and capable of realizing high saturation.
2. Description of the Related Art
Various attempts were heretofore made to improve color reproduction in color reversal photographic materials.
In order to attain higher saturation and higher faithfulness in color reproduction, as for color negative films, correction of side absorption of coloring materials are generally made by masking in which so-called colored couplers are used. On the other hand, in the case of color reversal photographic materials, the above-mentioned correction of side absorption of coloring materials by means of masking using colored couplers cannot be carried out. Accordingly, attempts to improve color reproduction mainly by use of an interimage effect were made, as well as improvements in spectral sensitivity and spectral absorption characteristics of coloring materials.
For example, xe2x80x9cThe Theory of The Photographic Process, Fourth Editionxe2x80x9d, T. H. James, page 568 discloses that attaching much importance to faithful color reproduction will increase overlap in spectral sensitivities, especially, of GL and RL and will reduce saturation and, therefore, emphasis of a larger interimage effect is required for combining the faithful color reproduction and the saturation.
The interimage effect is described by W. T. Hanson Jr. et al. in Journal of the Optical Society of America, Vol. 42, pp. 663-669.
Examples of disclosed methods of enhancing the interimage effect in color reversal films are as follows: U.S. Pat. No. 4,082,553 discloses a reversal image-forming photographic element with a layer arrangement of a plurality of silver halide emulsion layers positioned to permit iodide ion migration among the emulsion layers upon development, in which a surface-fogged silver halide emulsion is added in a lightsensitive emulsion layer.
Jpn. Pat. KOKOKU Publication No. (hereinafter referred to as JP-B-) 1-60135 discloses a color reversal photographic material comprising a blue-, green- and red-sensitive layers, in which each of these layers has sub-layers differing in speed, in which the ratio of the coating silver amount of a high-speed layer, or both a high-speed layer and a medium-speed layer, to the amount of a low-speed layer, is regulated, and in which the silver iodide content of a high-speed layer, or both a high-speed layer and a medium-speed layer, to the content of a low-speed layer, is regulated, thereby to improve the interimage effect. Further, U.S. Pat. No. 5,262,287 discloses a color reversal photographic material, wherein the total silver halide lightsensitive grains have an average iodide content of 5.5 mol % or less, wherein the color reversal photographic material comprises means for expressing an interimage effect, and wherein the degrees of the interimage effect at color densities of 0.5 and 1.5 are regulated.
Such means for enhancing the interimage effect is fundamentally based on changing in the silver iodide content of a lightsensitive silver halide emulsion contained in an image-forming layer, and it, therefore, is accompanied by adverse effects such as deterioration of sensitivity of the silver halide emulsion contained in the image-forming layer and deterioration of preservative properties. Accordingly, there is a limit of enhancement achieved by such means.
Japanese Patent Nos. 2547587, and 2549102, EP 0898200A1 and so on provide a technology to enhance the interimage effect without causing the aforementioned adverse effects by forming a substantially no-dye-forming interimage effect-donating layer. According to this approach, the interimage effect can be enhanced with a few adverse effects. However, no description is made to a method for improving the faithful color reproduction and also in the above-mentioned problems.
With respect to lightsensitive emulsion layers and interimage effect-donating layers, preferable spectral sensitivity distributions for realizing faithful color reproduction are disclosed in Jpn. Pat. Appln. KOKAI Publication No. (hereinafter referred to as JP-A-) 02-272540 and JP-A""s-03-122636, 03-264935, 02-124566 and so on.
Although both faithful color reproduction and saturation can be compatible to some extent if these approaches are employed, the degree of improvement is insufficient and some additional improvement is desired.
An object of the present invention is to realize a color reversal photographic material that is superior in faithful color reproduction and exhibits high saturation.
The object of the invention was attained by the following approaches.
(1) A silver halide color reversal photographic material comprising, on a transparent support, at least one blue-sensitive emulsion layer unit containing a color coupler that forms yellow color, at least one green-sensitive emulsion layer unit containing a color coupler that forms magenta color and at least one red-sensitive emulsion layer unit containing a color coupler that forms cyan color, wherein
the photographic material having means for regulating an interimage effect;
spectral sensitivity distribution of the red-sensitive emulsion layer unit satisfying the following relation:
620 nmxe2x89xa6xcexrmaxxe2x89xa6660 nm, 
wherein xcexrmax is the wavelength at which the maximum sensitivity of the spectral sensitivity distribution of the red-sensitive emulsion layer unit is given;
sensitivities of the red-sensitive emulsion layer unit and the green-sensitive emulsion layer unit satisfying the following relations:
Sr(xcexrmax)xe2x88x92Sr(580)xe2x89xa61.0 and 
xe2x88x920.5xe2x89xa6Sr(580)xe2x88x92Sg(580)xe2x89xa60.5 
xe2x80x83wherein Sr(xcexrmax) is the maximum sensitivity of the red-sensitive emulsion layer unit and Sr(580) is the sensitivity of the red-sensitive emulsion layer unit at 580 nm, and Sg(580) is the sensitivity of the green-sensitive emulsion layer unit at 580 nm; and
magnitude of the interimage effect between the red-sensitive emulsion layer unit and the green-sensitive emulsion layer unit satisfying the following relations:
IIEgrxe2x89xa70.15 and 
IIErgxe2x89xa70.0 
wherein IIEgr is the magnitude of the interimage effect from the green-sensitive emulsion layer unit to the red-sensitive emulsion layer unit, and IIErg is the magnitude of the interimage effect from the red-sensitive emulsion layer unit to the green-sensitive emulsion layer unit
(2) The silver halide color reversal photographic material recited in item (1) above, wherein
spectral sensitivity distribution of the green-sensitive emulsion layer unit satisfying the following relation:
520 nmxe2x89xa6xcexgmaxxe2x89xa6570 nm 
wherein xcexgmax is the wavelength at which the maximum sensitivity of the spectral sensitivity distribution of the green-sensitive emulsion layer unit is given;
xe2x80x83sensitivities of the green-sensitive emulsion layer unit satisfying the following relations:
Sg(500) greater than Sg(580) and 
xe2x80x830 less than Sg(xcexgmax)xe2x88x92Sg(500)xe2x89xa61.0
wherein Sg(500) is the sensitivity of the green-sensitive emulsion layer unit at 500 nm, Sg(580) is the sensitivity of the green-sensitive emulsion layer unit at 580 nm, and Sg(xcexgmax) is the maximum sensitivity of the green-sensitive emulsion layer unit; and
magnitude of the interimage effect between the green-sensitive emulsion layer unit and the blue-sensitive emulsion layer unit satisfying the following relations:
IIEbgxe2x89xa70.15 and 
IIEgbxe2x89xa70.0 
wherein IIEbg is the magnitude of the interimage effect from the blue-sensitive emulsion layer unit to the green-sensitive emulsion layer unit, and IIEgb is the magnitude of the interimage effect from the green-sensitive emulsion layer unit to the blue-sensitive emulsion layer unit
(3) The silver halide color reversal photographic material recited in item (1) or (2) above, wherein the means for regulating an interimage effect is at least one interimage effect-donating layer that contains a lightsensitive emulsion and that does not substantially form a color image.
(4) The silver halide color reversal photographic material recited in any one of items (1) to (3) above, wherein at least one green-sensitive emulsion layer of the green-sensitive emulsion layer unit containing at least one magenta coupler represented by the following general formula (MC-I) and/or at least one red-sensitive emulsion layer of the red-sensitive emulsion layer unit containing at least one cyan coupler represented by the following general formula (CC-I), and each of the amounts of the magenta coupler and the cyan coupler is 30 mol % or more and 100 mol % or less with respect to a image-forming coupler contained in the green-sensitive emulsion layer and the red-sensitive emulsion layer, respectively. 
In formula (MC-I), R1 represents a hydrogen atom or substituent; one of G1 and G2 represents a carbon atom, and the other represents a nitrogen atom; and R2 represents a substituent that substitutes one of G1 and G2 which is a carbon atom. R1 and R2 may further have a substituent. X represents a hydrogen atom or a group that is capable of splitting off by a coupling reaction with an aromatic primary amine color developing agent in an oxidized form. 
In formula (CC-I), Ga represents xe2x80x94C(R13)xe2x95x90 or xe2x80x94Nxe2x95x90. When Ga represents xe2x80x94Nxe2x95x90, Gb represents xe2x80x94C(R13)xe2x95x90, and when Ga represents xe2x80x94C(R13)xe2x95x90, Gb represents xe2x80x94Nxe2x95x90.
Each of R11 and R12 represents an electron-withdrawing group having a Hammett substituent constant "sgr"p value of 0.20 to 1.0. R13 represents a substituent. Y represents a hydrogen atom or a group that is capable of splitting off by a coupling reaction with an aromatic primary amine color developing agent in an oxidized form.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.